Question

The number of reflexive relations on a set with four elements is equal to

Answer 1

Answer:

Input : n = 2

Output : 4

The given set A = {1, 2}. The following

are reflexive relations on A * A :

{{1, 1), (2, 2)}

{(1, 1), (2, 2), (1, 2)}

{(1, 1), (2, 2), (1, 2), (2, 1)}

{(1, 1), (2, 2), (2, 1)}

Input : n = 3

Output : 64

The given set is {1, 2, 3}. There are

64 reflexive relations on A * A :

Explanation :

Reflexive Relation : A Relation R on A a set A is said to be Reflexive if xRx for every element of x ? A